EP0466546A1 - Winch with friction wheels - Google Patents

Winch with friction wheels Download PDF

Info

Publication number
EP0466546A1
EP0466546A1 EP91401718A EP91401718A EP0466546A1 EP 0466546 A1 EP0466546 A1 EP 0466546A1 EP 91401718 A EP91401718 A EP 91401718A EP 91401718 A EP91401718 A EP 91401718A EP 0466546 A1 EP0466546 A1 EP 0466546A1
Authority
EP
European Patent Office
Prior art keywords
pressure
pump
wheels
hydraulic motors
flow divider
Prior art date
Legal status (The legal status is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the status listed.)
Withdrawn
Application number
EP91401718A
Other languages
German (de)
French (fr)
Inventor
Jacques Lanau
Current Assignee (The listed assignees may be inaccurate. Google has not performed a legal analysis and makes no representation or warranty as to the accuracy of the list.)
Kley-France SA
Kley France
Original Assignee
Kley-France SA
Kley France
Priority date (The priority date is an assumption and is not a legal conclusion. Google has not performed a legal analysis and makes no representation as to the accuracy of the date listed.)
Filing date
Publication date
Application filed by Kley-France SA, Kley France filed Critical Kley-France SA
Publication of EP0466546A1 publication Critical patent/EP0466546A1/en
Withdrawn legal-status Critical Current

Links

Images

Classifications

    • B—PERFORMING OPERATIONS; TRANSPORTING
    • B66—HOISTING; LIFTING; HAULING
    • B66D—CAPSTANS; WINCHES; TACKLES, e.g. PULLEY BLOCKS; HOISTS
    • B66D3/00—Portable or mobile lifting or hauling appliances
    • B66D3/003—Portable or mobile lifting or hauling appliances using two or more cooperating endless chains

Definitions

  • the present invention relates to a winch with grip wheels, of the type comprising n (n ⁇ 2) pairs of wheels, the two wheels of each pair acting, in service, on opposite longitudinal surfaces of a cable to which a pulling force must be applied, a variable displacement pump, a flow divider circuit having an inlet connected to the discharge side of the pump and n outlets to divide the flow of hydraulic fluid supplied by the pump into n equal flows, n pairs of hydraulic motors respectively mechanically coupled to the wheels to drive them in rotation, the two hydraulic motors of each pair being hydraulically connected in a series circuit, of which a first end is connected to a respective output among the n outputs of the flow divider circuit and of which the second end is connected to a hydraulic fluid tank to which the suction side of the pump is also connected.
  • the wheels are in principle identical, it may happen that in service they have different diameters, for example because of greater wear of a wheel compared to the others and / or, in the case of wheels fitted with pneumatic tires, because the tire of one wheel is more or less inflated than those of other wheels.
  • the slip of a wheel on the cable can cause wear of the cable and / or the wheel or its tire as already indicated above, it can also result from it that the wheel which slips n do not apply the desired tensile force to the cable.
  • the object of the present invention is therefore to provide a winch with grip wheels of the above-mentioned type, in which the circuit for supplying hydraulic fluid to the hydraulic wheel drive motors makes it possible to obtain better synchronization of the tangential speeds. of said wheels.
  • the winch of the present invention is characterized in that it further comprises an auxiliary pump, the discharge side of which is hydraulically connected in parallel to the first ends of the n series circuits formed by the n pairs of hydraulic motors, through n respective intake valves, and in that the midpoints of said series circuits, between the two hydraulic motors of each pair, are connected to a point on the circuit which, in service is at a pressure equal to or substantially equal to the pressure working pressure on the discharge side of the variable displacement pump, through a pressure reducer which, in service, determines at all said medium points a reduced pressure which is in a predetermined relationship with the working pressure on the discharge side of the variable displacement, said ratio being such that the difference in pressures between the first end and the midpoint of any one of said series circuits is equal to the difference in pressures between said midpoint and the second end of the same series circuit.
  • the flow divider circuit can comprise, in a known manner, n hydraulic motors whose rotors are coupled to a common shaft and whose intake orifices are connected in common to form the inlet of the flow divider circuit, the discharge orifices of said motors respectively forming the outputs of the flow divider circuit.
  • the auxiliary pump can be mechanically coupled to said common shaft to be driven by it.
  • the pressure reducer can be connected to each of said midpoints through a throttle in parallel with a non-return valve, the passing direction of which is directed towards the corresponding midpoint.
  • the discharge side of the auxiliary pump can also be connected to the tank at through a pressure limiter controlled by the working pressure of the variable displacement pump.
  • the winch shown in the drawing comprises two pairs of wheels 1a, 2a and 1b, 2b which can be driven in rotation respectively by hydraulic motors 3a, 4a and 3b, 4b.
  • the wheels 1a and 2a are respectively supported by arms 5a and 6a, which can pivot around axes 7a and 8a.
  • the two arms 5a and 6a can be selectively attracted towards each other or separated from each other by means of a hydraulic or pneumatic cylinder 9a, in order to apply the two wheels 1a and 2a against the surfaces opposite of a cable 10 to which a tensile force must be applied, or in order to separate them therefrom.
  • the pivoting movements of the two arms 5a and 6a towards each other or one away from the other are synchronized by two toothed sectors 11a and 12a which are integral in rotation with the two arms.
  • the two wheels 1b and 2b are supported by an assembly similar to that which has just been described with regard to the two wheels 1a and 2a. This is why only part of the two support arms 5b and 6b of the wheels 1b and 2b has been shown.
  • the hydraulic motors 3a, 4a, 3b, 4b can be supplied with hydraulic fluid by a hydraulic supply circuit comprising a reservoir 13, a variable displacement pump 14, driven by a motor 15, such as an electric motor, and a divider or flow distributor circuit 16.
  • the orifice the pump 14 is connected to the reservoir 13 through a filter 17, while its discharge orifice is connected by a pipe 18 to the inlet 19 of the flow divider 16, which has two outlets 21a and 21b (one output by pair of hydraulic motors 3, 4).
  • the flow divider 16 can be essentially constituted by two hydraulic motors 16a and 16b, which are identical and mechanically coupled to a common shaft 22, so that, in service, they divide the flow of the hydraulic fluid supplied by the pump 14 at two substantially equal flow rates.
  • the two hydraulic motors 3a and 4a are hydraulically connected in series and this series circuit is connected on the one hand to the outlet 21a of the flow divider 16 and on the other hand to the return pipe 23 which brings the fluid used to the reservoir 13
  • the hydraulic motors 3b and 4b are hydraulically connected in series and this series circuit and connected on the one hand to the outlet 21b of the flow divider 16 and on the other hand to the return line 23.
  • the hydraulic motors 3a and 4a, as well as the hydraulic motors 3b and 4b are hydraulically connected in such a way that the motors of each pair rotate in opposite directions of rotation so that the wheels 1 and 2 to which they are coupled respectively have tangential speeds pointing in the same direction in the region where the wheels are in contact with the cable 10.
  • the motors 3a, 4a, 3b and 4b are reversible hydraulic motors and direction reversing valves 24a and 24b are inserted respectively in the series supply circuit of motors 3a and 4a and in the series supply circuit of motors 3b and 4b.
  • the circuit may include an on / off distributor 25, with two channels, which is inserted in the lines 18 and 23; a balancer 26 (pressure balance), which is inserted in the return line 23 and which is controlled by a pilot solenoid valve 27; a pressure relief valve 28, which is connected to the discharge port of the pump 14 and which acts as a safety valve; another pressure limiter 29, a filter 31 and a heat exchanger 32, which are inserted in series, in this order, in the return pipe 23 between the on / off distributor 25 and the reservoir 13.
  • the pressure limiter 29 is provided to establish a booster back pressure for the motors 3a, 4a, 3b and 4b.
  • the outputs 21a and 21b of the two hydraulic motors 16a and 16b forming the flow divider 16 are connected respectively by isolation valves 33a and 33b to a pressure relief valve 34. In this way, identical pressures are obtained at the outputs 21a and 21b.
  • the hydraulic circuit further comprises an auxiliary pump 35, the suction port of which is connected to the reservoir 13 and the discharge port of which is connected in parallel to the series supply circuit of the motors 3a and 4a through an intake valve 36a and to the series supply circuit of the motors 3b and 4b through an intake valve 36b.
  • the discharge port of the auxiliary pump 35 is also connected to points 37a and 37b, which are located respectively between the motors 3a and 4a and between the motors 3b and 4b, through a pressure reducer 38, which, in use, is controlled by the working pressure of pump 14 and which has for function of establishing a reduced pressure at the two points 37a and 37b.
  • the pressure reducer 38 is adjusted so that the pressure is reduced in a predetermined ratio with the working pressure of the pump 14. This ratio is such that the same pressure difference prevails between the inlet and the outlet of all motors 3a, 4a, 3b and 4b.
  • P N designates the working pressure of the pump 14 (pressure prevailing at the outputs 21a and 21b of the flow divider 16)
  • P G the booster backpressure defined by the limiter 29 and P R said reduced pressure ( pressure prevailing at points 37a and 37b)
  • variable displacement pump 14 can be a pump capable of providing an adjustable flow rate from 0 to 200 l / min under a working pressure P N of 260 bars
  • the auxiliary pump 35 can be a fixed displacement capable of delivering a flow rate of 10 l / min under the same working pressure P N.
  • the pressure relief valve 29 is adjusted to a pressure P G of 20 bars
  • the reduced pressure P R desired at points 37a and 37b is therefore equal to 140 bars.
  • the pressure reducer 38 is then adjusted so as to have a reduction ratio equal to 0.538.
  • the pump 35 can be conveniently rotated by the shaft 22.
  • the pressure reducer 38 is connected to point 37a through a throttle 39a in parallel with a non-return valve 41a, and to point 37b through a throttle 39b in parallel with a non-return valve 41b.
  • Valves 41a and 41b make sense passer-by directed respectively to point 37a and point 37b.
  • the discharge orifice of the auxiliary pump 35 is also connected to the reservoir 13 through a pressure limiter 42 controlled by the working pressure of the pump 14.
  • the inlet valve 36a opens and lets part of the flow from the auxiliary pump 35 to the motor 3a, thus causing an increase in the speed of rotation of this motor, which restores the desired tangential speed for wheel 1a. If the wheel 2a has a tangential speed equal to or greater than the desired speed, the compensation flow which has been supplied by the auxiliary pump 35 and which has passed through the motor 3a, or the excess flow is evacuated towards the reservoir 13 to through the throttle 39a and the pressure reducer 38.
  • the tangential speed of the wheel 2a also has a value less than the desired value, for example because of a reduction in the diameter of this wheel, at least part of the compensation flow which has been supplied by the auxiliary pump 35 and which has passed through the motor 3a also passes through the motor 4a. If this is insufficient to restore the desired tangential speed for the wheel 2a, an additional part of the flow from the auxiliary pump 35 is sent to the motor 4a through the pressure reducer 38 and the valve 41a. The excess flow from the auxiliary pump 35 is returned to the reservoir 13 through the pressure relief valve 42.
  • a flow divider 16 having a greater number of outlets, each outlet supplying two hydraulic motors in series for driving a pair of corresponding wheels, the discharge orifice of the auxiliary pump 35 being connected by a respective inlet valve 36 to a respective outlet 21 to each series circuit formed by a pair of hydraulic motors 3, 4, and also at the midpoints of said series circuits, between the two hydraulic motors of each pair, through the pressure reducer 38.
  • the flow divider 16 may then include as many hydraulic motors as there are pairs of wheels, all the hydraulic motors of the divider 16 being coupled to the common shaft 22. It will also be noted that the auxiliary pump 35, instead of being driven by the shaft 22, could be driven by the motor 15.
  • the pressure reducer 38 can be hydraulically connected not to the auxiliary pump 35, but to the pump 14.
  • the connection 43 is eliminated and the pressure reducer can be connected for example at point 19 by the link 44 shown in phantom in the figure.

Landscapes

  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Control Of Fluid Gearings (AREA)

Abstract

In this winch, which comprises a number of pairs of friction wheels (1a, 2a; 1b, 2b; and so on) driven by respective hydraulic motors (3a, 4a; 3b, 4b; and so on) which are fed with hydraulic fluid by a pump (14) and by a flow-dividing circuit (16), the two hydraulic motors (3, 4) of each pair being connected hydraulically in a series circuit, an auxiliary pump (35) is moreover provided, the lift side of which is connected hydraulically in parallel to a first end of each of the series circuits formed by the pairs of hydraulic motors (3a, 4a; 3b, 4b; and so on), through the respective admission flaps (36a, 36b, and so on), and to the middle points (37a, 37b, and so on) of said series circuits, between the two hydraulic motors of each pair, through a pressure reducer (38) which, in service, brings about in all said middle points a reduced pressure which is in a predetermined ratio with the working pressure on the lift side of the pump (14) of variable capacity. <IMAGE>

Description

La présente invention concerne un treuil à roues d'adhérence, du type comprenant n (n ≧ 2) paires de roues, les deux roues de chaque paire agissant, en service, sur des surfaces longitudinales opposées d'un câble auquel une force de traction doit être appliquée, une pompe à cylindrée variable, un circuit diviseur de débit ayant une entrée reliée au côté refoulement de la pompe et n sorties pour diviser l'écoulement du fluide hydraulique fourni par la pompe en n écoulements égaux, n paires de moteurs hydrauliques respectivement accouplés mécaniquement aux roues pour les entraîner en rotation, les deux moteurs hydrauliques de chaque paire étant reliés hydrauliquement en un circuit série, dont une première extrémité est reliée à une sortie respective parmi les n sorties du circuit diviseur de débit et dont la seconde extrémité est reliée à un réservoir de fluide hyraulique auquel est également relié le côté aspiration de la pompe.The present invention relates to a winch with grip wheels, of the type comprising n (n ≧ 2) pairs of wheels, the two wheels of each pair acting, in service, on opposite longitudinal surfaces of a cable to which a pulling force must be applied, a variable displacement pump, a flow divider circuit having an inlet connected to the discharge side of the pump and n outlets to divide the flow of hydraulic fluid supplied by the pump into n equal flows, n pairs of hydraulic motors respectively mechanically coupled to the wheels to drive them in rotation, the two hydraulic motors of each pair being hydraulically connected in a series circuit, of which a first end is connected to a respective output among the n outputs of the flow divider circuit and of which the second end is connected to a hydraulic fluid tank to which the suction side of the pump is also connected.

Dans les treuils connus de ce genre, il est essentiel que les deux roues de chaque paire de roues soient synchronisées en vitesse tangentielle, de même que toutes les paires de roues les unes par rapport aux autres. En effet, si une roue avait une vitesse tangentielle différente de celle des autres roues, elle aurait tendance à patiner sur le câble, provoquant alors une usure du câble et/ou de la roue elle-même. C'est pour cela que les deux moteurs hydrauliques entraînant chaque paire de roues sont reliés hydrauliquement en série, et que les diverses paires de moteurs hydrauliques sont alimentées en parallèle en fluide hydraulique par l'intermédiaire du circuit diviseur de débit, qui délivre à ses sorties des débits égaux pour toutes les paires de moteurs hydrauliques.In known winches of this kind, it is essential that the two wheels of each pair of wheels are synchronized in tangential speed, as are all the pairs of wheels with respect to each other. Indeed, if a wheel had a tangential speed different from that of the other wheels, it would tend to slip on the cable, causing wear of the cable and / or of the wheel itself. This is why the two hydraulic motors driving each pair of wheels are hydraulically connected in series, and that the various pairs of hydraulic motors are supplied with fluid in parallel. hydraulic through the flow divider circuit, which delivers equal flow rates to all pairs of hydraulic motors.

Bien que, en théorie, avec un tel circuit diviseur de débit les moteurs hydrauliques et les roues correspondantes devraient tous tourner à la même vitesse et que, par conséquent, les roues, qui sont en principe identiques, devraient toutes avoir la même vitesse périphérique, l'expérience a néanmoins montré qu'il arrive parfois qu'une ou plusieurs roues ont tendance à patiner sur le câble. Cela peut être dû à diverses raisons, par exemple à des débits de fuite différents dans les divers moteurs hydrauliques d'entraînement des roues, ou encore à des défauts localisés de surface du câble. En outre, même si les roues tournent exactement à la même vitesse, elles n'ont pas nécessairement la même vitesse tangentielle si les roues ont des diamètres différents. Or, bien que les roues soient en principe identiques, il peut arriver qu'en service elles présentent des diamètres différents, par exemple à cause d'une plus grande usure d'une roue par rapport aux autres et/ou, dans le cas de roues équipées de bandages pneumatiques, parce que le pneumatique d'une roue est plus gonflé ou moins gonflé que ceux des autres roues. En plus du fait que le patinage d'une roue sur le câble peut entraîner une usure du câble et/ou de la roue ou de son bandage comme cela a déjà été indiqué plus haut, il peut aussi en résulter que la roue qui patine n'applique pas l'effort désiré de traction au câble.Although, in theory, with such a flow divider circuit the hydraulic motors and the corresponding wheels should all rotate at the same speed and therefore the wheels, which are in principle identical, should all have the same peripheral speed, However, experience has shown that sometimes one or more wheels tend to slip on the cable. This can be due to various reasons, for example to different leakage rates in the various hydraulic wheel drive motors, or to localized cable surface defects. Furthermore, even if the wheels rotate at exactly the same speed, they do not necessarily have the same tangential speed if the wheels have different diameters. However, although the wheels are in principle identical, it may happen that in service they have different diameters, for example because of greater wear of a wheel compared to the others and / or, in the case of wheels fitted with pneumatic tires, because the tire of one wheel is more or less inflated than those of other wheels. In addition to the fact that the slip of a wheel on the cable can cause wear of the cable and / or the wheel or its tire as already indicated above, it can also result from it that the wheel which slips n do not apply the desired tensile force to the cable.

La présente invention a donc pour but de fournir un treuil à roues d'adhérence du type sus-indiqué, dans lequel le circuit d'alimentation en fluide hyraulique des moteurs hydrauliques d'entraînement des roues permet d'obtenir une meilleure synchronisation des vitesses tangentielles desdites roues.The object of the present invention is therefore to provide a winch with grip wheels of the above-mentioned type, in which the circuit for supplying hydraulic fluid to the hydraulic wheel drive motors makes it possible to obtain better synchronization of the tangential speeds. of said wheels.

A cet effet, le treuil de la présente invention est caractérisé en ce qu'il comprend en outre une pompe auxiliaire, dont le côté refoulement est relié hydrauliquement en parallèle aux premières extrémités des n circuits série formés par les n paires de moteurs hydrauliques, à travers n clapets d'admission respectifs, et en ce que les points milieux desdits circuits série, entre les deux moteurs hydrauliques de chaque paire, sont reliés à un point du circuit qui, en service est à une pression égale ou sensiblement égale à la pression de travail aqu côté refoulement de la pompe à cylindrée variable, à travers un réducteur de pression qui, en service, détermine en tous lesdits points milieux une pression réduite qui est dans un rapport prédéterminé avec la pression de travail au côté refoulement de la pompe à cylindrée variable, ledit rapport étant tel que la différence des pressions entre la première extrémité et le point milieu de l'un quelconque desdits circuits série soit égale à la différence des pressions entre ledit point milieu et la seconde extrémité du même circuit série.To this end, the winch of the present invention is characterized in that it further comprises an auxiliary pump, the discharge side of which is hydraulically connected in parallel to the first ends of the n series circuits formed by the n pairs of hydraulic motors, through n respective intake valves, and in that the midpoints of said series circuits, between the two hydraulic motors of each pair, are connected to a point on the circuit which, in service is at a pressure equal to or substantially equal to the pressure working pressure on the discharge side of the variable displacement pump, through a pressure reducer which, in service, determines at all said medium points a reduced pressure which is in a predetermined relationship with the working pressure on the discharge side of the variable displacement, said ratio being such that the difference in pressures between the first end and the midpoint of any one of said series circuits is equal to the difference in pressures between said midpoint and the second end of the same series circuit.

Suivant une forme d'exécution de l'invention, le circuit diviseur de débit peut comprendre, de façon connue, n moteurs hydrauliques dont les rotors sont accouplés à un arbre commun et dont les orifices d'admission sont reliés en commun pour former l'entrée du circuit diviseur de débit, les orifices de décharge desdits moteurs formant respectivement les sorties du circuit diviseur de débit. Dans ce cas, la pompe auxiliaire peut être accouplée mécaniquement audit arbre commun pour être entraînée par lui. Le réducteur de pression peut être relié à chacun desdits points milieux à travers un étranglement en parallèle avec un clapet anti-retour, dont le sens passant est dirigé vers le point milieu correspondant. Le côté refoulement de la pompe auxiliaire peut être en outre relié au réservoir à travers un limiteur de pression asservi à la pression de travail de la pompe à cylindrée variable.According to one embodiment of the invention, the flow divider circuit can comprise, in a known manner, n hydraulic motors whose rotors are coupled to a common shaft and whose intake orifices are connected in common to form the inlet of the flow divider circuit, the discharge orifices of said motors respectively forming the outputs of the flow divider circuit. In this case, the auxiliary pump can be mechanically coupled to said common shaft to be driven by it. The pressure reducer can be connected to each of said midpoints through a throttle in parallel with a non-return valve, the passing direction of which is directed towards the corresponding midpoint. The discharge side of the auxiliary pump can also be connected to the tank at through a pressure limiter controlled by the working pressure of the variable displacement pump.

D'autres caractéristiques et avantages de l'invention ressortiront au cours de la description qui va suivre d'une forme d'exécution de l'invention, donnée à titre d'exemple en référence à la figure unique du dessin annexé, qui représente le schéma hydraulique de principe d'un treuil à roues d'adhérence conforme à la présente invention.Other characteristics and advantages of the invention will emerge during the following description of an embodiment of the invention, given by way of example with reference to the single figure of the appended drawing, which represents the hydraulic schematic diagram of a winch with grip wheels according to the present invention.

Le treuil représenté sur le dessin comprend deux paires de roues 1a, 2a et 1b, 2b qui peuvent être entraînées en rotation respectivement par des moteurs hydrauliques 3a, 4a et 3b, 4b.The winch shown in the drawing comprises two pairs of wheels 1a, 2a and 1b, 2b which can be driven in rotation respectively by hydraulic motors 3a, 4a and 3b, 4b.

Les roues 1a et 2a sont respectivement supportées par des bras 5a et 6a, qui peuvent pivoter autour d'axes 7a et 8a. Les deux bras 5a et 6a peuvent être sélectivement attirés l'un vers l'autre ou écartés l'un de l'autre au moyen d'un vérin hydraulique ou pneumatique 9a, afin d'appliquer les deux roues 1a et 2a contre les surfaces opposées d'un câble 10 auquel une force de traction doit être appliquée, ou afin de les en écarter. Les mouvements de pivotement des deux bras 5a et 6a l'un vers l'autre ou l'un à l'écart de l'autre sont synchronisés par deux secteurs dentés 11a et 12a qui sont solidaires en rotation des deux bras.The wheels 1a and 2a are respectively supported by arms 5a and 6a, which can pivot around axes 7a and 8a. The two arms 5a and 6a can be selectively attracted towards each other or separated from each other by means of a hydraulic or pneumatic cylinder 9a, in order to apply the two wheels 1a and 2a against the surfaces opposite of a cable 10 to which a tensile force must be applied, or in order to separate them therefrom. The pivoting movements of the two arms 5a and 6a towards each other or one away from the other are synchronized by two toothed sectors 11a and 12a which are integral in rotation with the two arms.

Les deux roues 1b et 2b sont supportées par un montage similaire à celui qui vient d'être décrit à propos des deux roues 1a et 2a. C'est pourquoi on a seulement représenté une partie des deux bras de support 5b et 6b des roues 1b et 2b.The two wheels 1b and 2b are supported by an assembly similar to that which has just been described with regard to the two wheels 1a and 2a. This is why only part of the two support arms 5b and 6b of the wheels 1b and 2b has been shown.

Les moteurs hydrauliques 3a, 4a, 3b, 4b peuvent être alimentés en fluide hydraulique par un circuit hydraulique d'alimentation comprenant un réservoir 13, une pompe 14 à cylindrée variable, entraînée par un moteur 15, tel qu'un moteur électrique, et un circuit diviseur ou répartiteur de débit 16. L'orifice d'aspiration de la pompe 14 est relié au réservoir 13 à travers un filtre 17, tandis que son orifice de refoulement est relié par une conduite 18 à l'entrée 19 du diviseur de débit 16, lequel possède deux sorties 21a et 21b (une sortie par paire de moteurs hydrauliques 3, 4).The hydraulic motors 3a, 4a, 3b, 4b can be supplied with hydraulic fluid by a hydraulic supply circuit comprising a reservoir 13, a variable displacement pump 14, driven by a motor 15, such as an electric motor, and a divider or flow distributor circuit 16. The orifice the pump 14 is connected to the reservoir 13 through a filter 17, while its discharge orifice is connected by a pipe 18 to the inlet 19 of the flow divider 16, which has two outlets 21a and 21b (one output by pair of hydraulic motors 3, 4).

Comme montré dans la figure, le diviseur de débit 16 peut être essentiellement constitué par deux moteurs hydrauliques 16a et 16b, qui sont identiques et accouplés mécaniquement à un arbre commun 22, de telle façon que, en service, ils divisent le débit du fluide hydraulique fourni par la pompe 14 en deux débits sensiblement égaux.As shown in the figure, the flow divider 16 can be essentially constituted by two hydraulic motors 16a and 16b, which are identical and mechanically coupled to a common shaft 22, so that, in service, they divide the flow of the hydraulic fluid supplied by the pump 14 at two substantially equal flow rates.

Les deux moteurs hydrauliques 3a et 4a sont reliés hydrauliquement en série et ce circuit série est relié d'une part à la sortie 21a du diviseur de débit 16 et d'autre part à la conduite de retour 23 qui ramène le fluide utilisé au réservoir 13. De même, les moteurs hydrauliques 3b et 4b sont reliés hydrauliquement en série et ce circuit série et relié d'une part à la sortie 21b du diviseur de débit 16 et d'autre part à la conduite de retour 23. On notera que les moteurs hydrauliques 3a et 4a, de même que les moteurs hydrauliques 3b et 4b sont raccordés hydrauliquement de telle manière que les moteurs de chaque paire tournent dans des sens de rotation opposés pour que les roues 1 et 2 auxquelles ils sont respectivement accouplés aient des vitesses tangentielles dirigées dans le même sens dans la région où les roues sont en contact avec le câble 10.The two hydraulic motors 3a and 4a are hydraulically connected in series and this series circuit is connected on the one hand to the outlet 21a of the flow divider 16 and on the other hand to the return pipe 23 which brings the fluid used to the reservoir 13 Similarly, the hydraulic motors 3b and 4b are hydraulically connected in series and this series circuit and connected on the one hand to the outlet 21b of the flow divider 16 and on the other hand to the return line 23. It will be noted that the hydraulic motors 3a and 4a, as well as the hydraulic motors 3b and 4b are hydraulically connected in such a way that the motors of each pair rotate in opposite directions of rotation so that the wheels 1 and 2 to which they are coupled respectively have tangential speeds pointing in the same direction in the region where the wheels are in contact with the cable 10.

Dans le cas où chaque roue doit pouvoir être entraînée sélectivement dans l'un ou l'autre sens de rotation selon le sens dans lequel le câble 10 doit être déplacé, les moteurs 3a, 4a, 3b et 4b sont des moteurs hydrauliques réversibles et des distributeurs d'inversion de sens de marche 24a et 24b sont insérés respectivement dans le circuit série d'alimentation des moteurs 3a et 4a et dans le circuit série d'alimentation des moteurs 3b et 4b.In the case where each wheel must be able to be driven selectively in one or the other direction of rotation depending on the direction in which the cable 10 must be moved, the motors 3a, 4a, 3b and 4b are reversible hydraulic motors and direction reversing valves 24a and 24b are inserted respectively in the series supply circuit of motors 3a and 4a and in the series supply circuit of motors 3b and 4b.

Pour compléter le circuit d'alimentation des moteurs hydrauliques 3a, 4a, 3b, 4b, le circuit peut comporter un distributeur de marche/arrêt 25, à deux voies, qui est inséré dans les conduites 18 et 23; un équilibreur 26 (balance de pression), qui est inséré dans la conduite de retour 23 et qui est piloté par une électrovalve pilote 27; un limiteur de pression 28, qui est relié à l'orifice de refoulement de la pompe 14 et qui joue le rôle de soupape de sécurité; un autre limiteur de pression 29, un filtre 31 et un échangeur de chaleur 32, qui sont insérés en série, dans cet ordre, dans la conduite de retour 23 entre le distributeur de marche/arrêt 25 et le réservoir 13. Le limiteur de pression 29 est prévu pour établir une contre-pression de gavage pour les moteurs 3a, 4a, 3b et 4b. Les sorties 21a et 21b des deux moteurs hydrauliques 16a et 16b formant le diviseur de débit 16 sont reliées respectivement par des clapets d'isolement 33a et 33b à un limiteur de pression 34. De cette manière, on obtient des pressions identiques aux sorties 21a et 21b.To complete the supply circuit of the hydraulic motors 3a, 4a, 3b, 4b, the circuit may include an on / off distributor 25, with two channels, which is inserted in the lines 18 and 23; a balancer 26 (pressure balance), which is inserted in the return line 23 and which is controlled by a pilot solenoid valve 27; a pressure relief valve 28, which is connected to the discharge port of the pump 14 and which acts as a safety valve; another pressure limiter 29, a filter 31 and a heat exchanger 32, which are inserted in series, in this order, in the return pipe 23 between the on / off distributor 25 and the reservoir 13. The pressure limiter 29 is provided to establish a booster back pressure for the motors 3a, 4a, 3b and 4b. The outputs 21a and 21b of the two hydraulic motors 16a and 16b forming the flow divider 16 are connected respectively by isolation valves 33a and 33b to a pressure relief valve 34. In this way, identical pressures are obtained at the outputs 21a and 21b.

Conformément à la présente invention, le circuit hydraulique comprend en outre une pompe auxiliaire 35, dont l'orifice d'aspiration est relié au réservoir 13 et dont l'orifice de refoulement est relié en parallèle au circuit série d'alimentation des moteurs 3a et 4a à travers un clapet d'admission 36a et au circuit série d'alimentation des moteurs 3b et 4b à travers un clapet d'admission 36b. L'orifice de refoulement de la pompe auxiliaire 35 est également relié aux points 37a et 37b, qui se trouvent respectivement entre les moteurs 3a et 4a et entre les moteurs 3b et 4b, à travers un réducteur de pression 38, qui, en service, est asservi à la pression de travail de la pompe 14 et qui a pour fonction d'établir une pression réduite aux deux points 37a et 37b. Plus précisément, le réducteur de pression 38 est réglé pour que la pression soit réduite dans un rapport prédéterminé avec la pression de travail de la pompe 14. Ce rapport est tel que la même différence de pression règne entre l'entrée et la sortie de tous les moteurs 3a, 4a, 3b et 4b. Autrement dit, si P N désigne la pression de travail de la pompe 14 (pression régnant aux sorties 21a et 21b du diviseur de débit 16), P G la contre-pression de gavage définie par le limiteur 29 et P R ladite pression réduite (pression régnant aux points 37a et 37b), on doit avoir:According to the present invention, the hydraulic circuit further comprises an auxiliary pump 35, the suction port of which is connected to the reservoir 13 and the discharge port of which is connected in parallel to the series supply circuit of the motors 3a and 4a through an intake valve 36a and to the series supply circuit of the motors 3b and 4b through an intake valve 36b. The discharge port of the auxiliary pump 35 is also connected to points 37a and 37b, which are located respectively between the motors 3a and 4a and between the motors 3b and 4b, through a pressure reducer 38, which, in use, is controlled by the working pressure of pump 14 and which has for function of establishing a reduced pressure at the two points 37a and 37b. More precisely, the pressure reducer 38 is adjusted so that the pressure is reduced in a predetermined ratio with the working pressure of the pump 14. This ratio is such that the same pressure difference prevails between the inlet and the outlet of all motors 3a, 4a, 3b and 4b. In other words, if P N designates the working pressure of the pump 14 (pressure prevailing at the outputs 21a and 21b of the flow divider 16), P G the booster backpressure defined by the limiter 29 and P R said reduced pressure ( pressure prevailing at points 37a and 37b), there must be:

P N - P R = P R - P G
ce qui peut encore s'écrire:P N - P R = P R - P G
which can still be written:

P R = 1/2 (P N + P G ) ou encore : P R /P N = 1/2 + P G /2P N P R = 1/2 (P N + P G ) or: P R / P N = 1/2 + P G / 2P N

D'après la formule ci-dessus, on voit immédiatement que si P G est petit par rapport à P N , comme cela est usuellement le cas, le rapport du réducteur de pression 38 est environ égal à 1/2.From the above formula, it is immediately seen that if P G is small compared to P N , as is usually the case, the ratio of the pressure reducer 38 is approximately equal to 1/2.

A titre d'exemple, la pompe 14 à cylindrée variable peut être une pompe capable de fournir un débit réglable de 0 à 200 l/min sous une pression de travail P N de 260 bars, et la pompe auxiliaire 35 peut être une pompe à cylindrée fixe capable de fournir un débit de 10 l/min sous la même pression de travail P N . En supposant que le limiteur de pression 29 est réglé à une pression P G de 20 bars, la pression réduite P R désirée aux points 37a et 37b est donc égale à 140 bars. Le réducteur de pression 38 est alors réglé de manière à avoir un rapport de réduction égal à 0,538. La pompe 35 peut être commodément entraînée en rotation par l'arbre 22.By way of example, the variable displacement pump 14 can be a pump capable of providing an adjustable flow rate from 0 to 200 l / min under a working pressure P N of 260 bars, and the auxiliary pump 35 can be a fixed displacement capable of delivering a flow rate of 10 l / min under the same working pressure P N. Assuming that the pressure relief valve 29 is adjusted to a pressure P G of 20 bars, the reduced pressure P R desired at points 37a and 37b is therefore equal to 140 bars. The pressure reducer 38 is then adjusted so as to have a reduction ratio equal to 0.538. The pump 35 can be conveniently rotated by the shaft 22.

De préférence, le réducteur de pression 38 est relié au point 37a à travers un étranglement 39a en parallèle avec un clapet anti-retour 41a, et au point 37b à travers un étranglement 39b en parallèle avec un clapet anti-retour 41b. Les clapets 41a et 41b ont un sens passant dirigé respectivement vers le point 37a et le point 37b.Preferably, the pressure reducer 38 is connected to point 37a through a throttle 39a in parallel with a non-return valve 41a, and to point 37b through a throttle 39b in parallel with a non-return valve 41b. Valves 41a and 41b make sense passer-by directed respectively to point 37a and point 37b.

Enfin l'orifice de refoulement de la pompe auxiliaire 35 est en outre relié au réservoir 13 à travers un limiteur de pression 42 asservi à la pression de travail de la pompe 14.Finally, the discharge orifice of the auxiliary pump 35 is also connected to the reservoir 13 through a pressure limiter 42 controlled by the working pressure of the pump 14.

On décrira maintenant le fonctionnement du treuil de la présente invention. Quand les paires de roues 1a, 2a; 1b, 2b;... sont appliquées sur le câble 10 par les vérins respectifs 9a,..., tant que toutes les roues ont des rayons égaux (rayon en charge mesuré dans la région où les roues sont en contact avec le câble), le débit de fluide hydraulique nécessaire pour faire tourner les moteurs hyrauliques 3a, 4a, 3b, 4b,... à la vitesse de rotation correspondant à la vitesse tangentielle désirée pour toutes les roues, est fourni seulement par la pompe 14, tandis que le fluide hydraulique fourni par la pompe auxiliaire 35 est renvoyé au réservoir 13 à travers le limiteur de pression 42. Par contre, si, pour une raison quelconque, le rayon de l'une quelconque des roues, par exemple celui de la roue 1a, vient à diminuer, il faut alors augmenter la vitesse de rotation de la roue la concernée, donc du moteur 3a correspondant, afin de maintenir la vitesse tangentielle de ladite roue à la valeur désirée (on rappellera que la vitesse tangentielle d'une roue est égale au produit du rayon de la roue par sa vitesse de rotation). Dans l'hypothèse où le rayon de la roue 1a a diminué, le couple fourni par cette roue a diminué, donc également la pression de travail du moteur 3a, de sorte que la pression à la sortie 21a du diviseur de débit 16 devient plus faible que la pression à la sortie de la pompe auxiliaire 35. Il en résulte que le clapet d'admission 36a s'ouvre et laisse passer une partie du débit de la pompe auxiliaire 35 vers le moteur 3a, provoquant ainsi une augmentation de la vitesse de rotation de ce moteur, qui rétablit la vitesse tangentielle désirée pour la roue 1a. Si la roue 2a a une vitesse tangentielle égale ou plus grande que la vitesse désirée, le débit de compensation qui a été fourni par la pompe auxiliaire 35 et qui a traversé le moteur 3a, ou le surplus de débit est évacué vers le réservoir 13 à travers l'étranglement 39a et le réducteur de pression 38. Par contre, si la vitesse tangentielle de la roue 2a a elle aussi une valeur inférieure à la valeur désirée, par exemple à cause d'une diminution du diamètre de cette roue, au moins une partie du débit de compensation qui a été fourni par la pompe auxiliaire 35 et qui a traversé le moteur 3a traverse également le moteur 4a. Si cela est insuffisant pour rétablir la vitesse tangentielle désirée pour la roue 2a, une partie supplémentaire du débit de la pompe auxiliaire 35 est envoyée au moteur 4a à travers le réducteur de pression 38 et le clapet 41a. Le surplus de débit de la pompe auxiliaire 35 est renvoyé au réservoir 13 à travers le limiteur de pression 42.The operation of the winch of the present invention will now be described. When the pairs of wheels 1a, 2a; 1b, 2b; ... are applied to the cable 10 by the respective cylinders 9a, ..., as long as all the wheels have equal radii (radius under load measured in the region where the wheels are in contact with the cable) , the flow rate of hydraulic fluid necessary to rotate the hydraulic motors 3a, 4a, 3b, 4b, ... at the speed of rotation corresponding to the tangential speed desired for all the wheels, is supplied only by the pump 14, while the hydraulic fluid supplied by the auxiliary pump 35 is returned to the reservoir 13 through the pressure limiter 42. On the other hand, if, for any reason, the radius of any one of the wheels, for example that of the wheel 1a, comes to decrease, it is then necessary to increase the speed of rotation of the wheel concerned, therefore of the corresponding motor 3a, in order to maintain the tangential speed of said wheel at the desired value (it will be recalled that the tangential speed of a wheel is equal to ray product of the wheel by its speed of rotation). In the event that the radius of the wheel 1a has decreased, the torque supplied by this wheel has decreased, therefore also the working pressure of the motor 3a, so that the pressure at the outlet 21a of the flow divider 16 becomes lower as the pressure at the outlet of the auxiliary pump 35. As a result, the inlet valve 36a opens and lets part of the flow from the auxiliary pump 35 to the motor 3a, thus causing an increase in the speed of rotation of this motor, which restores the desired tangential speed for wheel 1a. If the wheel 2a has a tangential speed equal to or greater than the desired speed, the compensation flow which has been supplied by the auxiliary pump 35 and which has passed through the motor 3a, or the excess flow is evacuated towards the reservoir 13 to through the throttle 39a and the pressure reducer 38. On the other hand, if the tangential speed of the wheel 2a also has a value less than the desired value, for example because of a reduction in the diameter of this wheel, at least part of the compensation flow which has been supplied by the auxiliary pump 35 and which has passed through the motor 3a also passes through the motor 4a. If this is insufficient to restore the desired tangential speed for the wheel 2a, an additional part of the flow from the auxiliary pump 35 is sent to the motor 4a through the pressure reducer 38 and the valve 41a. The excess flow from the auxiliary pump 35 is returned to the reservoir 13 through the pressure relief valve 42.

Toujours dans l'hypothèse où la roue 1a a un rayon qui a diminué, si la roue 1b a un rayon plus grand que celui de la roue 1a, donc aussi une vitesse tangentielle plus grande que celle de la roue 1a à vitesses égales de rotation, le couple fourni par la roue 1b est alors plus grand que le couple fourni par la roue 1a. Il en résulte que la pression de travail du moteur 3b est plus grande que celle du moteur 3a, provoquant ainsi l'ouverture du clapet 33b et la fermeture du clapet 33a. Une partie du débit à la sortie 21b du diviseur de débit 16 est alors dérivée vers le reservoir 13 à travers le clapet 33b et le limiteur de pression 34. Ceci réduit le débit qui traverse le moteur 3b, donc aussi sa vitesse de rotation et, par suite, la vitesse tangentielle de la roue 1b est réduite. Il en est de même pour la roue 2b.Still on the assumption that the wheel 1a has a radius which has decreased, if the wheel 1b has a larger radius than that of the wheel 1a, therefore also a tangential speed greater than that of the wheel 1a at equal speeds of rotation , the torque supplied by the wheel 1b is then greater than the torque supplied by the wheel 1a. As a result, the working pressure of the motor 3b is greater than that of the motor 3a, thus causing the valve 33b to open and the valve 33a to close. Part of the flow at the outlet 21b of the flow divider 16 is then diverted to the reservoir 13 through the valve 33b and the pressure limiter 34. This reduces the flow passing through the motor 3b, therefore also its speed of rotation and, as a result, the tangential speed of the wheel 1b is reduced. The same is true for wheel 2b.

On voit donc que si une roue comme la roue 1a a une vitesse tangentielle plus petite que celle des autres roues, l'égalisation des vitesses tangentielles est obtenue à la fois par une augmentation de la vitesse de rotation de la roue 1a (grâce à la pompe auxiliaire 35 qui envoie un débit supplémentaire au moteur 3a à travers le clapet d'admission 36a) et par une diminution de la vitesse de rotation des autres roues (par une réduction du débit envoyé aux moteurs correspondants). On notera que si cela avait été la roue 2a ou 2b qui avait une vitesse tangentielle plus petite que celle des autres roues, l'augmentation de la vitesse de rotation de la roue 2a ou 2b aurait été obtenue par l'envoi d'un débit supplémentaire au moteur 4a ou 4b par la pompe auxiliaire 35 à travers le réducteur de pression 38 et le clapet 41a ou 41b.We therefore see that if a wheel like wheel 1a has a tangential speed smaller than that of the others wheels, the equalization of the tangential speeds is obtained at the same time by an increase in the speed of rotation of the wheel 1a (thanks to the auxiliary pump 35 which sends an additional flow to the engine 3a through the intake valve 36a) and by a reduction in the speed of rotation of the other wheels (by a reduction in the flow rate sent to the corresponding motors). Note that if it had been wheel 2a or 2b which had a tangential speed smaller than that of the other wheels, the increase in the speed of rotation of wheel 2a or 2b would have been obtained by sending a flow additional to the motor 4a or 4b by the auxiliary pump 35 through the pressure reducer 38 and the valve 41a or 41b.

Il va de soi que la forme d'exécution de l'invention qui a été décrite ci-dessus a été donnée à titre d'exemple purement indicatif et nullement limitatif, et que de nombreuses modifications peuvent être facilement apportées par l'homme de l'art sans pour autant sortir du cadre de la présente invention. C'est ainsi notamment que, bien que l'invention ait été décrite ci-dessus à propos d'un treuil comportant deux paires de roues, l'invention peut être facilement généralisée à un treuil comportant un plus grand nombre de paires de roues. Il suffit pour cela de prévoir un diviseur de débit 16 ayant un plus grand nombre de sorties, chaque sortie alimentant deux moteurs hydrauliques en série pour l'entraînement d'une paire de roues correspondantes, l'orifice de refoulement de la pompe auxiliaire 35 étant relié par un clapet d'admission respectif 36 à une sortie respective 21 vers chaque circuit série formé par une paire de moteurs hydrauliques 3, 4, et également aux points milieux desdits circuits série, entre les deux moteurs hydrauliques de chaque paire, à travers le réducteur de pression 38. Le diviseur de débit 16 pourra alors comprendre autant de moteurs hydrauliques que de paires de roues, tous les moteurs hydrauliques du diviseur 16 étant accouplés à l'arbre commun 22. On notera également que la pompe auxiliaire 35, au lieu d'être entraînée par l'arbre 22, pourrait être entraînée par le moteur 15. Suivant une variante, le réducteur de pression 38 peut être relié hydrauliquement non pas à la pompe auxiliaire 35, mais à la pompe 14. Dans ce dernier cas, la liaison 43 est supprimée et le réducteur de pression peut être relié par exemple au point 19 par la liaison 44 montrée en trait mixte dans la figure.It goes without saying that the embodiment of the invention which has been described above has been given by way of purely indicative and in no way limitative example, and that numerous modifications can be easily made by those skilled in the art. art without departing from the scope of the present invention. Thus, in particular, although the invention has been described above with regard to a winch comprising two pairs of wheels, the invention can be easily generalized to a winch comprising a greater number of pairs of wheels. To do this, it suffices to provide a flow divider 16 having a greater number of outlets, each outlet supplying two hydraulic motors in series for driving a pair of corresponding wheels, the discharge orifice of the auxiliary pump 35 being connected by a respective inlet valve 36 to a respective outlet 21 to each series circuit formed by a pair of hydraulic motors 3, 4, and also at the midpoints of said series circuits, between the two hydraulic motors of each pair, through the pressure reducer 38. The flow divider 16 may then include as many hydraulic motors as there are pairs of wheels, all the hydraulic motors of the divider 16 being coupled to the common shaft 22. It will also be noted that the auxiliary pump 35, instead of being driven by the shaft 22, could be driven by the motor 15. Next a variant, the pressure reducer 38 can be hydraulically connected not to the auxiliary pump 35, but to the pump 14. In the latter case, the connection 43 is eliminated and the pressure reducer can be connected for example at point 19 by the link 44 shown in phantom in the figure.

Claims (7)

1.- Treuil à roues d'adhérence comprenant n (n ≧ 2) paires de roues (1a,2a; 1b,2b;...), les deux roues (1,2) de chaque paire agissant, en service, sur des surfaces longitudinales opposées d'un câble (10) auquel une force de traction doit être appliquée, une pompe (14) à cylindrée variable, un circuit diviseur de débit (16) ayant une entrée (19) reliée au côté refoulement de la pompe (14) et n sorties (21a, 21b,...) pour diviser l'écoulement du fluide hydraulique fourni par la pompe en n écoulements égaux, n paires de moteurs hydrauliques (3a,4a; 3b, 4b;...) respectivement accouplés mécaniquement aux roues pour les entraîner en rotation, les deux moteurs hydrauliques (3,4) de chaque paire étant reliés hydrauliquement en un circuit série, dont une première extrémité est reliée à une sortie respective parmi les n sorties (21a, 21b,...) du circuit diviseur de débit (16) et dont la seconde extrémité est reliée à un réservoir de fluide hydraulique (13) auquel est également relié le côté aspiration de la pompe (14), caractérisé en ce qu'il comprend en outre une pompe auxiliaire (35), dont le côté refoulement est relié hydrauliquement en parallèle aux premières extrémités des n circuits série formés par les n paires de moteurs hydrauliques (3a, 4a; 3b, 4b;...), à travers n clapets d'admission respectifs (36a, 36b,...), et en ce que les points milieux (37a, 37b,...) desdits circuits série, entre les deux moteurs hydrauliques de chaque paire, sont reliés à un point du circuit (43 ou 44) qui, en service, est à une pression égale ou sensiblement égale à la pression de travail au côté refoulement de la pompe (14) à cylindrée variable, à travers un réducteur de pression (38) qui, en service, détermine en tous lesdits points milieux une pression réduite qui est dans un rapport prédéterminé avec ladite pression de travail, ledit rapport étant tel que la différence des pressions entre la première extrémité et le point milieu de l'un quelconque desdits circuits série soit égale à la différence des pressions entre ledit point milieu et la seconde extrémité du même circuit série. 1.- Winch with grip wheels comprising n (n ≧ 2) pairs of wheels (1a, 2a; 1b, 2b; ...), the two wheels (1,2) of each pair acting, in service, on opposite longitudinal surfaces of a cable (10) to which a pulling force is to be applied, a variable displacement pump (14), a flow divider circuit (16) having an inlet (19) connected to the discharge side of the pump (14) and n outlets (21a, 21b, ...) to divide the flow of hydraulic fluid supplied by the pump into n equal flows, n pairs of hydraulic motors (3a, 4a; 3b, 4b; ...) respectively mechanically coupled to the wheels to drive them in rotation, the two hydraulic motors (3,4) of each pair being hydraulically connected in a series circuit, a first end of which is connected to a respective outlet among the n outlets (21a, 21b, ...) of the flow divider circuit (16) and the second end of which is connected to a hydraulic fluid reservoir (13) to which el is also connected the suction side of the pump (14), characterized in that it further comprises an auxiliary pump (35), the discharge side of which is hydraulically connected in parallel to the first ends of the n series circuits formed by the n pairs of hydraulic motors (3a, 4a; 3b, 4b; ...), through n respective intake valves (36a, 36b, ...), and in that the midpoints (37a, 37b, ...) of said series circuits, between the two hydraulic motors of each pair, are connected to a point on the circuit (43 or 44) which, in service, is at an equal or substantially equal pressure at the working pressure on the discharge side of the variable displacement pump (14), through a pressure reducer (38) which, in service, determines at all said midpoints a reduced pressure which is in a predetermined relationship with said pressure of work, said ratio being such that the difference in pressures between the first end and the midpoint of any one of said series circuits is equal to the difference in pressures between said midpoint and the second end of the same series circuit. 2. - Treuil selon la revendication 1, caractérisé en ce que le réducteur de pression est relié (par 43) au côté refoulement de la pompe auxiliaire (35). 2. - Winch according to claim 1, characterized in that the pressure reducer is connected (by 43) to the discharge side of the auxiliary pump (35). 3.- Treuil selon la revendication 1, caractérisé en ce que le réducteur de pression est relié (par 44) au côté refoulement de la pompe (14) à cylindrée variable. 3. Winch according to claim 1, characterized in that the pressure reducer is connected (by 44) to the discharge side of the variable displacement pump (14). 4.- Treuil selon l'une quelconque des revendications 1 à 3, caractérisé en ce que le circuit diviseur de débit (16) comprend, de façon connue, n moteurs hydrauliques (16a, 16b...), dont les rotors sont accouplés à un arbre commun (22) et dont les orifices d'admission sont reliés en commun pour former l'entrée (19) du circuit diviseur de débit, les orifices de décharge desdits moteurs formant respectivement les sorties (21a, 21b,...) du circuit diviseur de débit, et en ce que la pompe auxiliaire (35) est accouplée mécaniquement audit arbre commun (22) pour être entraînée par lui. 4. Winch according to any one of claims 1 to 3, characterized in that the flow divider circuit (16) comprises, in known manner, n hydraulic motors (16a, 16b ...), whose rotors are coupled to a common shaft (22) and the inlet ports of which are connected in common to form the inlet (19) of the flow divider circuit, the discharge ports of said motors respectively forming the outlets (21a, 21b, ... ) of the flow divider circuit, and in that the auxiliary pump (35) is mechanically coupled to said common shaft (22) to be driven by it. 5.- Treuil selon l'une quelconque des revendications 1 à 4, caractérisé en ce que le côté refoulement de la pompe auxiliaire (35) est en outre relié au réservoir (13) à travers un limiteur de pression (42) asservi à la pression de travail de la pompe (14) à cylindrée variable. 5. Winch according to any one of claims 1 to 4, characterized in that the delivery side of the auxiliary pump (35) is also connected to the reservoir (13) through a pressure limiter (42) controlled by the working pressure of the variable displacement pump (14). 6.- Treuil selon l'une quelconque des revendications 1 à 5, caractérisé en ce que le réducteur de pression (38) est relié à chacun desdits points milieux (37a,37b,...) à travers un étranglement (39a,39b,...) en parallèle avec un clapet anti-retour (41a, 41b,...) dont le sens passant est dirigé vers le point milieu correspondant. 6. Winch according to any one of claims 1 to 5, characterized in that the pressure reducer (38) is connected to each of said middle points (37a, 37b, ...) through a throttle (39a, 39b, ...) in parallel with a non-return valve (41a, 41b, ...) whose the passing direction is directed towards the corresponding midpoint. 7.- Treuil selon l'une quelconque des revendications 1 à 6, caractérisé en ce que les sorties (21a, 21b,...) du circuit diviseur de débit (16) sont reliées par des clapets anti-retour respectifs (33a,33b,...) à un limiteur de pression (34). 7. Winch according to any one of claims 1 to 6, characterized in that the outputs (21a, 21b, ...) of the flow divider circuit (16) are connected by respective non-return valves (33a, 33b, ...) to a pressure relief valve (34).
EP91401718A 1990-07-03 1991-06-26 Winch with friction wheels Withdrawn EP0466546A1 (en)

Applications Claiming Priority (2)

Application Number Priority Date Filing Date Title
FR9008372A FR2664252A1 (en) 1990-07-03 1990-07-03 WINCH WITH ADHERENCE WHEELS.
FR9008372 1990-07-03

Publications (1)

Publication Number Publication Date
EP0466546A1 true EP0466546A1 (en) 1992-01-15

Family

ID=9398267

Family Applications (1)

Application Number Title Priority Date Filing Date
EP91401718A Withdrawn EP0466546A1 (en) 1990-07-03 1991-06-26 Winch with friction wheels

Country Status (2)

Country Link
EP (1) EP0466546A1 (en)
FR (1) FR2664252A1 (en)

Cited By (2)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2366356A (en) * 2000-09-01 2002-03-06 Ransomes Jacobsen Ltd Hydraulic transmission
CN104176671A (en) * 2014-07-21 2014-12-03 山西晋城无烟煤矿业集团有限责任公司 Dispatching winch system

Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3465941A (en) * 1966-12-01 1969-09-09 Duchesne & Bossiere Cable hauling and releasing device
FR2054811A5 (en) * 1969-07-28 1971-05-07 Bretagne Atel Chantiers
FR2297184A1 (en) * 1975-01-13 1976-08-06 Post Office APPARATUS FOR HAULING CABLES OR OTHER EXTENDED BODIES
FR2484948A1 (en) * 1979-08-27 1981-12-24 France Etat DEVICE FOR HANDLING FROM A BOAT AN IMMERSE LOAD HITCHED TO THE END OF A CABLE

Patent Citations (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3465941A (en) * 1966-12-01 1969-09-09 Duchesne & Bossiere Cable hauling and releasing device
FR2054811A5 (en) * 1969-07-28 1971-05-07 Bretagne Atel Chantiers
FR2297184A1 (en) * 1975-01-13 1976-08-06 Post Office APPARATUS FOR HAULING CABLES OR OTHER EXTENDED BODIES
FR2484948A1 (en) * 1979-08-27 1981-12-24 France Etat DEVICE FOR HANDLING FROM A BOAT AN IMMERSE LOAD HITCHED TO THE END OF A CABLE

Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
GB2366356A (en) * 2000-09-01 2002-03-06 Ransomes Jacobsen Ltd Hydraulic transmission
GB2366356B (en) * 2000-09-01 2004-12-01 Ransomes Jacobsen Ltd A turf-care apparatus
CN104176671A (en) * 2014-07-21 2014-12-03 山西晋城无烟煤矿业集团有限责任公司 Dispatching winch system
CN104176671B (en) * 2014-07-21 2016-08-24 山西晋城无烟煤矿业集团有限责任公司 Car hauler system

Also Published As

Publication number Publication date
FR2664252A1 (en) 1992-01-10

Similar Documents

Publication Publication Date Title
FR2728324A1 (en) TRAINING UNIT, IN PARTICULAR FOR MOTOR VEHICLES
EP1420973B1 (en) Hydrostatic transmission device of a mobile machine
WO2014048841A2 (en) Vehicle with hydraulic assistance by transmitting torque from a driving axle to a driven axle
EP2491277B1 (en) Hydrostatic transmission device enabling improved braking
FR2685263A1 (en) MOBILE ENGINE HAVING FRONT AND REAR DRIVING HYDRAULIC ENGINES.
EP1010566B1 (en) Transmission device for a mobile machine with turning behaviour control valve
FR2771468A1 (en) CONTINUOUSLY ADJUSTABLE GEARBOX FOR MOTOR VEHICLE
FR2645932A1 (en) HYDROSTATIC-MECHANICAL TRANSMISSION WITH PROGRESSIVE ACTION WITH POWER DERIVATION
EP0466546A1 (en) Winch with friction wheels
FR2551144A1 (en) Speed-reducing compensation control device for a pump with variable cylinder capacity connected to an engine
EP2765309B1 (en) Improved double hydraulic machine comprising a distribution valve, and a drive system incorporating such a hydraulic machine
FR2509822A1 (en) CONTROL DEVICE, IN PARTICULAR FOR MOTOR VEHICLE ON RAILS FOR GEAR CHOICE AND ADHESION OPERATION, OR ADHESION ONLY, WITH SUBDIVISION MECHANISM
FR2861448A1 (en) Hydrostatic transmission device for mobile unit, has exchange authorization valve moved to exchange prohibition position by spring that is set at pressure that is lower than desired make-up line pressure
FR2716939A1 (en) Swing plate hydraulic motor.
FR2911941A1 (en) CONTROL SYSTEM FOR TRACTION TRANSMISSION AND HYDRAULIC MOTOR USING SAME.
FR2468815A1 (en) CONTROL VALVE, IN PARTICULAR FOR HYDROSTATIC PROPULSION SYSTEMS OF VEHICLES SUCH AS TRACTORS
FR2529524A1 (en) SERVO-DIRECTION FOR A MOTOR VEHICLE, COMPRISING A CONTROL VALVE FOR CREATING A REACTION PRESSURE
EP2742260B1 (en) Hydrostatic transmission device ensuring good driveability
EP1055844A1 (en) Continuous power dividing hydromechanical transmission for motor vehicles
FR2473423A1 (en) Variable diameter spherical type wheel - has hydrostatic transmission stub axle tilted by ram action to vary diameter
FR2464865A1 (en) Drive for mine gallery overhead suspension system - includes hydraulic pressure unit for friction wheel drive each end of drive unit
FR3019610A1 (en) HYDRAULIC ASSISTANCE SYSTEM FOR A VEHICLE
FR3090788A1 (en) Displacement management system for delimbing head
WO2019057924A1 (en) Reversible bypass hydraulic system
FR2488952A1 (en) HYDRAULIC CONTROL VALVE CIRCUIT FOR PIVOTING MECHANISM

Legal Events

Date Code Title Description
PUAI Public reference made under article 153(3) epc to a published international application that has entered the european phase

Free format text: ORIGINAL CODE: 0009012

AK Designated contracting states

Kind code of ref document: A1

Designated state(s): DE GB IT NL

STAA Information on the status of an ep patent application or granted ep patent

Free format text: STATUS: THE APPLICATION IS DEEMED TO BE WITHDRAWN

18D Application deemed to be withdrawn

Effective date: 19920716